From: Anssi Hannula <anssi.hannula@iki.fi>
To: Alan Stern <stern@rowland.harvard.edu>
Subject: Re: [REGRESSION] "USB: use kfifo to buffer usb-generic serial writes" causes gobi_loader to hang
Date: Mon, 22 Feb 2010 21:24:27 +0200
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On maanantai 22 helmikuu 2010 21:10:33 Alan Stern wrote:
> On Mon, 22 Feb 2010, Anssi Hannula wrote:
> > I guess that would suggest that the device doesn't allow the
> > initialization data to be broken into packets arbitrarily (though some
> > differences seem allowed, as the windows driver transmits them
> > differently).
> > 
> > Does this mean a tty interface is ill-suited for the microcode upload,
> > and instead qcserial should use the kernel's generic microcode upload
> > mechanism or the userspace should use libusb to do it?
> 
> I don't know.  Didn't the old successful code use a tty interface?

Yes, but does the tty interface guarantee that the data of one write call is 
sent as one packet to the device?

If I understood this correctly, it seems the changes have caused it to now 
concatenate short writes into one packet, which the device doesn't seem to 
like.

-- 
Anssi Hannula
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